1. Field of the Invention
This invention relates in general to a circuit for correcting distorted teletype characters.
2. Description of the Prior Art
It is known in systems for correcting distorted teletype characters to release a scanning process for the duration of a character by means of a start signal which precedes each character. Scanning pulses are thereby produced in chronological order depending upon the start signal which respectively scan the individual step changes of the character in the stage center. This allows the reversals and phase shifts to be obtained even in chronologically displaced signals and, thus, the individual step in distortedly arriving characters are respectively scanned such that the correct polarity of the step is determined with a high probability. The term reception latitude has been introduced which defines the largest distortion for which a receiver will barely be capable of reproducing all characters correctly. The theoretically obtainable reception latitude for Teletype characters is 50%. For the setting of the scanning pulse, a so-called reception setter is utilized which is known that allows displacement of the scanning points in time to be accurately set. Thereby, it is possible to recognize unilateral distortions which considerably exceed the permitted proportion rate and to compensate so that in those cases it is also possible to obtain perfect reception of the characters. In conventional Teletype apparatus, the reception setter is a component part of the Teletype machine. Newer Teletype equipment which operate with a sufficiently large reception latitude do not contain reception setters in the machines. However, particularly during single current transmission over lines having great lengths considerably greater distortions occur and it is necessary to provide an arrangement which corresponds in its operation to the reception setter which can be utilized by the user of the Teletype apparatus when required.